Variable Resolution, Monolithic
Resolver-to-Digital Converter
a
AD2S80A
FEATURES
FUNCTIONAL BLOCK DIAGRAM
Monolithic (BiMOS ll) Tracking R/D Converter
40-Lead DIP Package
44-Terminal LCC Package
10-,12-,14-, and 16-Bit Resolution Set by User
Ratiometric Conversion
Low Power Consumption: 300 mW Typ
Dynamic Performance Set by User
High Max Tracking Rate 1040 RPS (10 Bits)
Velocity Output
Industrial Temperature Range Versions
Military Temperature Range Versions
ESD Class 2 Protection (2,000 V Min)
/883 B Parts Available
AD2S80A
A3
SIN I/P
A1
A2
INTEGRATOR
O/P
SIG GND
R-2R
DAC
SEGMENT
SWITCHING
PHASE
COS I/P
ANALOG
GND
RIPPLE
CLK
SENSITIVE
DETECTOR
VCO DATA
TRANSFER
LOGIC
16-BIT UP/DOWN COUNTER
OUTPUT DATA LATCH
VCO I/P
DATA
LOAD
+12V
–12V
APPLICATIONS
DC Brushless and AC Motor Control
Process Control
16 DATA BITS
Numerical Control of Machine Tools
Robotics
Axis Control
PRODUCT HIGHLIGHTS
Military Servo Control
Monolithic. A one chip solution reduces the package size
required and increases the reliability.
GENERAL DESCRIPTION
Resolution Set by User. Two control pins are used to select
the resolution of the AD2S80A to be 10, 12, 14, or 16 bits allowing
the user to use the AD2S80A with the optimum resolution for
each application.
The AD2S80A is a monolithic 10-, 12-, 14-, or 16-bit tracking
resolver-to-digital converter contained in a 40-lead DIP or 44-
terminal LCC ceramic package. It is manufactured on a BiMOS
II process that combines the advantages of CMOS logic and
bipolar high accuracy linear circuits on the same chip.
Ratiometric Tracking Conversion. Conversion technique
provides continuous output position data without conversion
delay and is insensitive to absolute signal levels. It also provides
good noise immunity and tolerance to harmonic distortion on
the reference and input signals.
The converter allows users to select their own resolution and dynamic
performance with external components. This allows the users great
flexibility in defining the converter that best suits their system
requirements. The converter allows users to select the resolution
to be 10, 12, 14, or 16 bits and to track resolver signals rotating
at up to 1040 revs per second (62,400 rpm) when set to 10-bit
resolution.
Dynamic Performance Set by the User. By selecting exter-
nal resistor and capacitor values the user can determine bandwidth,
maximum tracking rate and velocity scaling of the converter to
match the system requirements. The external components
required are all low cost preferred value resistors and capacitors,
and the component values are easy to select using the simple
instructions given.
The AD2S80A converts resolver format input signals into a
parallel natural binary digital word using a ratiometric tracking
conversion method. This ensures high-noise immunity and toler-
ance of lead length when the converter is remote from the resolver.
Velocity Output. An analog signal proportional to velocity is
available and is linear to typically one percent. This can be used
in place of a velocity transducer in many applications to provide
loop stabilization in servo controls and velocity feedback data.
The 10-, 12-, 14- or 16-bit output word is in a three-state digital
logic available in 2 bytes on the 16 output data lines. BYTE
SELECT, ENABLE and INHIBIT pins ensure easy data trans-
fer to 8- and 16-bit data buses, and outputs are provided to
allow for cycle or pitch counting in external counters.
Low Power Consumption. Typically only 300 mW.
An analog signal proportional to velocity is also available and
can be used to replace a tachogenerator.
Military Product. The AD2S80A is available processed in
accordance with MIL-STD-883B, Class B.
The AD2S80A operates over 50 Hz to 20,000 Hz reference
frequency.
MODELS AVAILABLE
Information on the models available is given in the section
“Ordering Information.”
REV. B
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use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
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© Analog Devices, Inc., 2000